Yep. It works and it’s awesome. I use conversations on android devices and dino and gajim on desktops, various family members use siskin on iOS.

With zero app or server-software or provider lock-in, and an actual in-practice diversity of apps and providers, the whole thing seems pretty immune to enshittification.

Well within the budget of a private investigator or burglar or peeping-tom or abusive ex-partner.

No need to scale; plenty of privacy/security incursions don’t require mass-surveillance.

That said, I’d suggest that the attack does scale economically . Think war-driving but with one of these setups – cruising around in a van through a dense neighbourhood collecting short clips of cctv footage looking for something of interest.

[…] the attack is an extremely expensive nation state level operation that doesn’t scale.

About $250 at most. Quoting the linked page:

Below is a list of equipment we used for the experiments.

• (1) Software Defined Ratio (SDR): Ettus USRP B210 USRP, ~$2100.
• (2) Low Noise Amplifier (LNA): Foresight Intelligence FSTRFAMP06 LNA, ~$200.
• (3) Directional Antenna: A common outdoor Log-periodic directional antenna (LPDA), ~$15.
• (4) A laptop, of course.

Note that the equipment can be replaced with cheaper counterparts. For example, USRP B210 can be replaced with RTL-SDR that costs ~$30.

To reproduce the attack: our GitHub repository provides the codes and instructions for reproducing and understanding the attack. We have prepared a ready-to-use software tool that can produce real-time reconstructions of the eavesdropped videos with EM signal input from the USRP device.

I wonder when (if?) orbital radio receiver arrays (a la starlink) are sensitive and discriminating enough to be used for this type of attack.

No, the “distributor” is the part which runs on your portable device, receives the push notifications, and wakes up the target apps as necessary.

https://unifiedpush.org/developers/spec/definitions/

Conversations can be a unified push distibutor: https://unifiedpush.org/users/distributors/conversations/

…and I’d trust it (battery-wise) with that. I have an old tablet with conversations running without battery restrictions on it, and if I’m not actually picking it up and using it it regularly goes 1-2 weeks on an 80% battery charge before it dies, the whole time giving audible notifications for XMPP messages/calls (which I attend to on other devices).

Cryptpad:

• Full-on google docs / office365 / libreoffice type replacement with collaboration.
• E2EE
• The complexity means it doesn’t work well on mobile, takes a while to load on a slow connection, more frequent bugs. (3.5 MiB page transfer)
• Self-hosting is complicated.

Etherpad:

• A competent collaborative rich-text editor. Doesn’t do spreadsheets or presentations or […].
• Not E2EE (you need to trust that the server a bit more).
• Lightweight, works on slower connections, works alright on mobile. (1.7 MiB page transfer)
• Self-hosting quite simple.

PrivateBin:

• Super-simple plain-text/markdown pastebin. No editing possible once saved.
• E2EE
• Very small. Works fine on slow connections and mobile. (0.2 MiB page transfer)
• Self-hosting very simple.